Methylisothiazolinone is a known neurotoxin. In 2004, the European Scientific Committee on Cosmetic Products and Non-Food Products Intended for Consumers (SCCNFP) suggested that companies limit the maximum concentration to 0.01% (100 ppm). However, US companies are not required to follow this guideline.

It is known to be absorbed through skin. A study at the Pittsburgh School of Medicine concluded that "Prolonged exposure to low levels of MIT and related compounds may have damaging consequences to the developing nervous system."

Help! I have been tested and am highly allergic to Methylisothiazolinone...I have had a terrible case of excema under my arms since last fall. I am on my fifth medication, have removed all products that contain it (that I can determine) from my house, but just discovered I forgot about dish detergent! DAWN..yuk! What is a Kathon-free detergent I can purchase????

Methylisothiazolinone is a general biocide at high concentrations. Compounds like this are incorporated in paints for ship hulls to deter algae accumulation and barnacles. While not highly potent, it works by reacting with thiol groups on proteins, hence, it is not selective to any particular organism. The low concentrations in these products is the trick to make them "safe".

I've broke out in the most terrible case of contact dermatitis on my hands due to this isothiazoline ingredient. It also has the names: Kathon, Methylcloroisothiazolinone, Methlisothiazolinone. Anything with the word isothiazolinone in it is bad if you're allergic. I had a allergy patch test done to comfirm this for me. I found it's in the Brand Especially for Baby baby wipes and It's a 10 leave in conditioner I recently started using. I'm still researching to see what else it's in so my hands can get better. This stuff sucks!!

I have a severe Methlisothiazolinone allergy. I got a list of approved items from my dermatologist that is updated regularly. There are no approved dish soaps. I have to use gloves to wash dishes. What I have been disappointed by is that there are very few organics on the list. Even items where it's not listed in the ingredients are giving me issues. I have to adhere to the list specifically. It's put out by the American Contact Dermatitis Association Contact Allergen Management Program. Your dermatologist may have access to it.

The strucutre of methylisothiazolinone does not contain a benzene ring and has no structural homology with estrogen at all. Methylisothiazolinone destroys neurones by removing zinc from them thus causing a 'death cascade' leading to apoptosis.

I found out I was allergic to methylisothiazolinone when my company did renovations on our floor & started painting. Be warned, I foudn out too late that the preservative is also included in BEHR paint. After my face, lips & tongue swelled up to the size of a pumpkin with delightful leathery itchy skin, I went staright to the allergist, whom after about 6 months of insane testing, determined my allergy. Not only was I slathering the stuff on my face & hair everyday and wondering why my back & chest were always breaking out (rinsing Pantene out of my hair & onto my skin!), the paint incident pushed it over the top. This stuff is awful and my mom & I went on a phone crusade to determine ingredients in almost all of our household products (you can't even begin to believe how many every day products it's in! Always check labels!). I do appreciate that a lot of the companies offered me coupons or my money back, but a coupon won't help if I can't use the product to begin with. As stated above, be careful because it does come as many other names as well. Good luck.

@James, thanks for pointing that out; I didn't look closely enough at the chemical diagram. I saw a ring and thought benzene, but I see that the ring is completed with sulfur and nitrogen, not pure carbon, so it's not technically a benzene ring. I'll revise my article; thanks!

Hi. I have recently started using some new "eco-friendly, non toxic products". I won't mention the brand yet! I seem to have an allergy and have seen the dishwashing liquid contains methylisothiazolinone, 5-chloro-2-methyl-isothiazol-3(2h)-one. My lips are a bit swollen, tight chest and feeling stuffy and tight in the chest. Could this be an allergy to this ingredient? I am trying to do a process of elimination to find out what is causing this allergy! Thanks!

You mentioned checking out Seventh Generation products to avoid this chemical. Funny, because I decided to research methylisothiazolinone after reading it on Seventh Generation's dish liquid ingredient list! I say we all make our own soaps from herbal extracts and the like!